Centrifugal Force upon the Cell ' 337 
nuclei concerned therewith is violently disturbed, the comple- 
tion of the cell-wall as such does not take place. 
Stamen-Hairs of Tradescantia. 
The behaviour of cells of the stamen-hairs of Tradescantia 
in response to violent centrifugal force proved to be of much 
comparative interest. These cells lend themselves readily to 
this as well as to many other sorts of experimentation. 
By means of gypsum, young unopened buds were fastened 
in short pieces of glass-tubing just large enough in diameter 
to admit them. The tubes were then packed in the cylinders 
previously mentioned. After centrifugal action, the buds 
were removed from the tubes and kept upon wet filter-paper 
in a moist chamber where they remained fresh for two or 
more days, during which time the cells of the stamen-hairs 
divided as usual. For immediate observation after centrifugal 
action, a bud is opened and the stamen transferred to a slide. 
Fastening individual stamens or even sections through the 
bud upon the slide proved not only difficult and troublesome 
but also more or less injurious to the cells. 
With buds arranged in this way, the line of centrifugal 
force was coincident with the longitudinal axis of the majority 
of the hairs, while many others lay at various angles to the 
same, making possible a displacement in all directions in the 
same bud. 
We shall direct our attention first to cells still in the 
embryonic condition, i. e. capable of division. In all the 
younger cells of the hair, the nucleus, together with the 
movable cytoplasm and its inclusions, was forced into a dense 
mass in the lower end of the cell, while the vacuole or 
vacuoles were compelled to occupy the opposite end or half 
of the cell. In a short time after the cessation of centrifugal 
force a normal redistribution was effected. 
In any stage of karyokinesis between that of the spindle- 
and the telo-phase, the figure is often forced into an oblique 
position in the cell, and the arrangement of the chromosomes 
